#include "tracking.h"

int setdiff(int* a, int na, vector<int> b){
	int size = 0;
	map<int, int> bmap;
	
	for(int i = 0; i < b.size(); i++){
		bmap[b[i]] = i;
	}
	
	for(int i = 0; i < na; i++){
		if(bmap.find(a[i]) == bmap.end()){
			a[size] = a[i];
			size++;
		}
	}
	
	return size;
}